1. Field of the Invention
The present invention relates to an image recording device for recording image information of the original such as, e.g., a check, an ordinary document, etc. on a recording medium such as a microfilm or the like.
2. Related Background Art
This type of prior art image recording device will be exemplified by FIG. 16. FIG. 16 is a side elevation illustrating one mode of a subject conveying system of a photographing device 1 serving as an image recording device.
When subjects S are placed on a paper feed tray 2 inclined downwards, the subjects S are moved in an arrowed direction by dint of the gravitational force. These subjects S are fed while being singly separated by a paper feed roller 3 rotating clockwise in the FIGURE and a separation roller 4 rotating clockwise in the FIGURE. Next, a lower belt 7 wound on belt rollers 6, 11 and on tension roller 10 is driven with rotations of a lower driving roller 9. The subjects S are conveyed from the horizontal direction to the vertical direction, while an idle roller 5 and a guide unit 8 depress the subjects S on the lower belt 7. The subjects S pass between a pair of guide glasses 22 serving as an exposure section.
Then, both surfaces of the subject S are simultaneously illuminated with beams of a pair of illumination lamps 21 during a passage between the guide glasses 22. Nip rollers 12, 13 are provided above and under the guide glasses 22. Further, an upper belt 18 wound on belt rollers 15, 17 and on a tension roller 16 is driven with rotation of an upper driving roller 19. A conveying route of the subjects S passing through the guide glasses 22 is changed from the vertical direction to the horizontal direction, while an idler roller 14 pushes the subjects S on the upper belt 18. The subjects S advance in an arrowed direction and are ejected into a stacker 20.
By the way, the following is a reason why the conveying speed of the subject S is constant in the conventional example explained above. If the conveying speed is made variable, an exposure time during photographing is also varied, and it is therefore required that a light quantity be adjusted. Besides, there differ the position of the stacker 20 and the way how the subject S springs out during the ejection in accordance with the speeds. A troublesome problem arises, wherein the positional adjustment is needed. However, the checks, etc. are quickly mass-processed, and hence the conveying speed is preferably high. While on the other hand, there exists a possibility that a relatively thin ordinary sheet-like document, etc. may be damaged by an impingement when feeding the document between the paper feed roller and the separation roller that are rotating at a high velocity. Therefore, the paper is fed preferably at a low speed during photographing thereof. As described above, there is such a defect that the paper feed speed can not be changed to a speed optimal to each subject.